[ZODB-Dev] Memcache or ZEO cache (Re: ZEO and relstporage performance)

2009-10-14 Thread Jim Fulton
On Tue, Oct 13, 2009 at 8:30 PM, Shane Hathaway sh...@hathawaymix.org wrote: This leads to an interesting question.  Memcached or ZEO cache--which is better? For what? For relstorage? or for ZEO?  While memcached has a higher minimum performance penalty, it also has a lower maximum penalty,

Re: [ZODB-Dev] ZEO and relstporage performance

2009-10-14 Thread Ross J. Reedstrom
On Tue, Oct 13, 2009 at 06:30:31PM -0600, Shane Hathaway wrote: Laurence Rowe wrote: Shane's earlier benchmarks show MySQL to be the fastest RelStorage backend: http://shane.willowrise.com/archives/relstorage-10-and-measurements/ Yep, despite my efforts to put PostgreSQL on top. :-) It

Re: [ZODB-Dev] ZEO and relstporage performance

2009-10-14 Thread Shane Hathaway
Ross J. Reedstrom wrote: For my druthers, I just _trust_ PostgreSQL a lot more: the one MySQL DB I have that I use on an on-going basis is my MythTV media-pc. Once a month or so I have to repair a table. I've used PostgreSQL in professional high load production for years and never had a

Re: [ZODB-Dev] Memcache or ZEO cache (Re: ZEO and relstporage performance)

2009-10-14 Thread Shane Hathaway
Jim Fulton wrote: The most complicated logic in the ZEO cache, which would be just as complicated with another cache storage implementation and more complicated with a shared cache storage is making sure the cache doesn't have stale state. I probably need to look at memcache again, but every

Re: [ZODB-Dev] Memcache or ZEO cache (Re: ZEO and relstporage performance)

2009-10-14 Thread Jim Fulton
On Wed, Oct 14, 2009 at 2:48 PM, Shane Hathaway sh...@hathawaymix.org wrote: Jim Fulton wrote: ... The biggest problem with ZEO performance on the client side is that reads require round trips and that generally a client thread only knows to request one read at a time [1]_.  I plan to add an

Re: [ZODB-Dev] ZEO and relstporage performance

2009-10-14 Thread Ross J. Reedstrom
On Wed, Oct 14, 2009 at 02:20:50PM -0400, Benji York wrote: On Wed, Oct 14, 2009 at 1:08 PM, Ross J. Reedstrom reeds...@rice.edu wrote: shared caches: this is the main reason I've been looking at relstore: we're running many Zope FEs against one ZOE right now, and due to the nature of the

Re: [ZODB-Dev] ZEO and relstporage performance

2009-10-14 Thread Benji York
On Wed, Oct 14, 2009 at 3:38 PM, Ross J. Reedstrom reeds...@rice.edu wrote: On Wed, Oct 14, 2009 at 02:20:50PM -0400, Benji York wrote: We're actually set up w/ squid in front of the zope FEs, using IPC to talk to them all. The default behavior is just to respond w/ a CACHE MISS and use